/*
************************************************************************************************************************
*                                                      uC/OS-III
*                                                 The Real-Time Kernel
*
*                                  (c) Copyright 2009-2012; Micrium, Inc.; Weston, FL
*                           All rights reserved.  Protected by international copyright laws.
*
*                                                   MUTEX MANAGEMENT
*
* File    : OS_MUTEX.C
* By      : JJL
* Version : V3.03.01
*
* LICENSING TERMS:
* ---------------
*           uC/OS-III is provided in source form for FREE short-term evaluation, for educational use or
*           for peaceful research.  If you plan or intend to use uC/OS-III in a commercial application/
*           product then, you need to contact Micrium to properly license uC/OS-III for its use in your
*           application/product.   We provide ALL the source code for your convenience and to help you
*           experience uC/OS-III.  The fact that the source is provided does NOT mean that you can use
*           it commercially without paying a licensing fee.
*
*           Knowledge of the source code may NOT be used to develop a similar product.
*
*           Please help us continue to provide the embedded community with the finest software available.
*           Your honesty is greatly appreciated.
*
*           You can contact us at www.micrium.com, or by phone at +1 (954) 217-2036.
************************************************************************************************************************
*/

#define  MICRIUM_SOURCE
#include <os.h>

#ifdef VSC_INCLUDE_SOURCE_FILE_NAMES
const  CPU_CHAR  *os_mutex__c = "$Id: $";
#endif


#if OS_CFG_MUTEX_EN > 0u
/*
************************************************************************************************************************
*                                                   CREATE A MUTEX
*
* Description: This function creates a mutex.
*
* Arguments  : p_mutex       is a pointer to the mutex to initialize.  Your application is responsible for allocating
*                            storage for the mutex.
*
*              p_name        is a pointer to the name you would like to give the mutex.
*
*              p_err         is a pointer to a variable that will contain an error code returned by this function.
*
*                                OS_ERR_NONE                    if the call was successful
*                                OS_ERR_CREATE_ISR              if you called this function from an ISR
*                                OS_ERR_ILLEGAL_CREATE_RUN_TIME if you are trying to create the Mutex after you called
*                                                                 OSSafetyCriticalStart().
*                                OS_ERR_NAME                    if 'p_name'  is a NULL pointer
*                                OS_ERR_OBJ_CREATED             if the mutex has already been created
*                                OS_ERR_OBJ_PTR_NULL            if 'p_mutex' is a NULL pointer
*
* Returns    : none
************************************************************************************************************************
*/

void  OSMutexCreate ( OS_MUTEX  *p_mutex,
                      CPU_CHAR  *p_name,
                      OS_ERR    *p_err )
{
    CPU_SR_ALLOC();



#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return;
    }
#endif

#ifdef OS_SAFETY_CRITICAL_IEC61508
    if ( OSSafetyCriticalStartFlag == DEF_TRUE )
    {
        *p_err = OS_ERR_ILLEGAL_CREATE_RUN_TIME;
        return;
    }
#endif

#if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u
    if ( OSIntNestingCtr > ( OS_NESTING_CTR ) 0 )           /* Not allowed to be called from an ISR                   */
    {
        *p_err = OS_ERR_CREATE_ISR;
        return;
    }
#endif

#if OS_CFG_ARG_CHK_EN > 0u
    if ( p_mutex == ( OS_MUTEX * ) 0 )                      /* Validate 'p_mutex'                                     */
    {
        *p_err = OS_ERR_OBJ_PTR_NULL;
        return;
    }
#endif

    OS_CRITICAL_ENTER();
    p_mutex->Type              =  OS_OBJ_TYPE_MUTEX;        /* Mark the data structure as a mutex                     */
    p_mutex->NamePtr           =  p_name;
    p_mutex->OwnerTCBPtr       = ( OS_TCB       * ) 0;
    p_mutex->OwnerNestingCtr   = ( OS_NESTING_CTR ) 0;      /* Mutex is available                                     */
    p_mutex->TS                = ( CPU_TS        ) 0;
    p_mutex->OwnerOriginalPrio =  OS_CFG_PRIO_MAX;
    OS_PendListInit ( &p_mutex->PendList );                 /* Initialize the waiting list                            */

#if OS_CFG_DBG_EN > 0u
    OS_MutexDbgListAdd ( p_mutex );
#endif
    OSMutexQty++;

    OS_CRITICAL_EXIT_NO_SCHED();
    *p_err = OS_ERR_NONE;
}

/*$PAGE*/
/*
************************************************************************************************************************
*                                                   DELETE A MUTEX
*
* Description: This function deletes a mutex and readies all tasks pending on the mutex.
*
* Arguments  : p_mutex       is a pointer to the mutex to delete
*
*              opt           determines delete options as follows:
*
*                                OS_OPT_DEL_NO_PEND          Delete mutex ONLY if no task pending
*                                OS_OPT_DEL_ALWAYS           Deletes the mutex even if tasks are waiting.
*                                                            In this case, all the tasks pending will be readied.
*
*              p_err         is a pointer to a variable that will contain an error code returned by this function.
*
*                                OS_ERR_NONE                 The call was successful and the mutex was deleted
*                                OS_ERR_DEL_ISR              If you attempted to delete the mutex from an ISR
*                                OS_ERR_OBJ_PTR_NULL         If 'p_mutex' is a NULL pointer.
*                                OS_ERR_OBJ_TYPE             If 'p_mutex' is not pointing to a mutex
*                                OS_ERR_OPT_INVALID          An invalid option was specified
*                                OS_ERR_STATE_INVALID        Task is in an invalid state
*                                OS_ERR_TASK_WAITING         One or more tasks were waiting on the mutex
*
* Returns    : == 0          if no tasks were waiting on the mutex, or upon error.
*              >  0          if one or more tasks waiting on the mutex are now readied and informed.
*
* Note(s)    : 1) This function must be used with care.  Tasks that would normally expect the presence of the mutex MUST
*                 check the return code of OSMutexPend().
*
*              2) OSMutexAccept() callers will not know that the intended mutex has been deleted.
*
*              3) Because ALL tasks pending on the mutex will be readied, you MUST be careful in applications where the
*                 mutex is used for mutual exclusion because the resource(s) will no longer be guarded by the mutex.
************************************************************************************************************************
*/

#if OS_CFG_MUTEX_DEL_EN > 0u
OS_OBJ_QTY  OSMutexDel ( OS_MUTEX  *p_mutex,
                         OS_OPT     opt,
                         OS_ERR    *p_err )
{
    OS_OBJ_QTY     cnt;
    OS_OBJ_QTY     nbr_tasks;
    OS_PEND_DATA  *p_pend_data;
    OS_PEND_LIST  *p_pend_list;
    OS_TCB        *p_tcb;
    OS_TCB        *p_tcb_owner;
    CPU_TS         ts;
    CPU_SR_ALLOC();



#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return ( ( OS_OBJ_QTY ) 0 );
    }
#endif

#if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u
    if ( OSIntNestingCtr > ( OS_NESTING_CTR ) 0 )               /* Not allowed to delete a mutex from an ISR          */
    {
        *p_err = OS_ERR_DEL_ISR;
        return ( ( OS_OBJ_QTY ) 0 );
    }
#endif

#if OS_CFG_ARG_CHK_EN > 0u
    if ( p_mutex == ( OS_MUTEX * ) 0 )                          /* Validate 'p_mutex'                                 */
    {
        *p_err = OS_ERR_OBJ_PTR_NULL;
        return ( ( OS_OBJ_QTY ) 0 );
    }
    switch ( opt )                                              /* Validate 'opt'                                     */
    {
    case OS_OPT_DEL_NO_PEND:
    case OS_OPT_DEL_ALWAYS:
        break;

    default:
        *p_err =  OS_ERR_OPT_INVALID;
        return ( ( OS_OBJ_QTY ) 0 );
    }
#endif

#if OS_CFG_OBJ_TYPE_CHK_EN > 0u
    if ( p_mutex->Type != OS_OBJ_TYPE_MUTEX )                   /* Make sure mutex was created                        */
    {
        *p_err = OS_ERR_OBJ_TYPE;
        return ( ( OS_OBJ_QTY ) 0 );
    }
#endif

    OS_CRITICAL_ENTER();
    p_pend_list = &p_mutex->PendList;
    cnt         = p_pend_list->NbrEntries;
    nbr_tasks   = cnt;
    switch ( opt )
    {
    case OS_OPT_DEL_NO_PEND:                                /* Delete mutex only if no task waiting               */
        if ( nbr_tasks == ( OS_OBJ_QTY ) 0 )
        {
#if OS_CFG_DBG_EN > 0u
            OS_MutexDbgListRemove ( p_mutex );
#endif
            OSMutexQty--;
            OS_MutexClr ( p_mutex );
            OS_CRITICAL_EXIT();
            *p_err = OS_ERR_NONE;
        }
        else
        {
            OS_CRITICAL_EXIT();
            *p_err = OS_ERR_TASK_WAITING;
        }
        break;

    case OS_OPT_DEL_ALWAYS:                                            /* Always delete the mutex                 */
        p_tcb_owner = p_mutex->OwnerTCBPtr;                           /* Did we had to change the prio of owner? */
        if ( ( p_tcb_owner       != ( OS_TCB * ) 0 ) &&
                ( p_tcb_owner->Prio !=  p_mutex->OwnerOriginalPrio ) )
        {
            switch ( p_tcb_owner->TaskState )                         /* yes                                     */
            {
            case OS_TASK_STATE_RDY:
                OS_RdyListRemove ( p_tcb_owner );
                p_tcb_owner->Prio = p_mutex->OwnerOriginalPrio;  /* Lower owner's prio back                 */
                OS_PrioInsert ( p_tcb_owner->Prio );
                OS_RdyListInsertTail ( p_tcb_owner );            /* Insert owner in ready list at new prio  */
                break;

            case OS_TASK_STATE_DLY:
            case OS_TASK_STATE_SUSPENDED:
            case OS_TASK_STATE_DLY_SUSPENDED:
                p_tcb_owner->Prio = p_mutex->OwnerOriginalPrio;  /* Not in any pend list, change the prio   */
                break;

            case OS_TASK_STATE_PEND:
            case OS_TASK_STATE_PEND_TIMEOUT:
            case OS_TASK_STATE_PEND_SUSPENDED:
            case OS_TASK_STATE_PEND_TIMEOUT_SUSPENDED:
                OS_PendListChangePrio ( p_tcb_owner,             /* Owner is pending on another object      */
                                        p_mutex->OwnerOriginalPrio );
                break;

            default:
                OS_CRITICAL_EXIT();
                *p_err = OS_ERR_STATE_INVALID;
                return ( ( OS_OBJ_QTY ) 0 );
            }
        }

        ts = OS_TS_GET();                                             /* Get timestamp                           */
        while ( cnt > 0u )                                            /* Remove all tasks from the pend list     */
        {
            p_pend_data = p_pend_list->HeadPtr;
            p_tcb       = p_pend_data->TCBPtr;
            OS_PendObjDel ( ( OS_PEND_OBJ * ) ( ( void * ) p_mutex ),
                            p_tcb,
                            ts );
            cnt--;
        }
#if OS_CFG_DBG_EN > 0u
        OS_MutexDbgListRemove ( p_mutex );
#endif
        OSMutexQty--;
        OS_MutexClr ( p_mutex );
        OS_CRITICAL_EXIT_NO_SCHED();
        OSSched();                                                    /* Find highest priority task ready to run */
        *p_err = OS_ERR_NONE;
        break;

    default:
        OS_CRITICAL_EXIT();
        *p_err = OS_ERR_OPT_INVALID;
        break;
    }
    return ( nbr_tasks );
}
#endif

/*$PAGE*/
/*
************************************************************************************************************************
*                                                    PEND ON MUTEX
*
* Description: This function waits for a mutex.
*
* Arguments  : p_mutex       is a pointer to the mutex
*
*              timeout       is an optional timeout period (in clock ticks).  If non-zero, your task will wait for the
*                            resource up to the amount of time (in 'ticks') specified by this argument.  If you specify
*                            0, however, your task will wait forever at the specified mutex or, until the resource
*                            becomes available.
*
*              opt           determines whether the user wants to block if the mutex is not available or not:
*
*                                OS_OPT_PEND_BLOCKING
*                                OS_OPT_PEND_NON_BLOCKING
*
*              p_ts          is a pointer to a variable that will receive the timestamp of when the mutex was posted or
*                            pend aborted or the mutex deleted.  If you pass a NULL pointer (i.e. (CPU_TS *)0) then you
*                            will not get the timestamp.  In other words, passing a NULL pointer is valid and indicates
*                            that you don't need the timestamp.
*
*              p_err         is a pointer to a variable that will contain an error code returned by this function.
*
*                                OS_ERR_NONE               The call was successful and your task owns the resource
*                                OS_ERR_MUTEX_OWNER        If calling task already owns the mutex
*                                OS_ERR_OBJ_DEL            If 'p_mutex' was deleted
*                                OS_ERR_OBJ_PTR_NULL       If 'p_mutex' is a NULL pointer.
*                                OS_ERR_OBJ_TYPE           If 'p_mutex' is not pointing at a mutex
*                                OS_ERR_OPT_INVALID        If you didn't specify a valid option
*                                OS_ERR_PEND_ABORT         If the pend was aborted by another task
*                                OS_ERR_PEND_ISR           If you called this function from an ISR and the result
*                                                          would lead to a suspension.
*                                OS_ERR_PEND_WOULD_BLOCK   If you specified non-blocking but the mutex was not
*                                                          available.
*                                OS_ERR_SCHED_LOCKED       If you called this function when the scheduler is locked
*                                OS_ERR_STATE_INVALID      If the task is in an invalid state
*                                OS_ERR_STATUS_INVALID     If the pend status has an invalid value
*                                OS_ERR_TIMEOUT            The mutex was not received within the specified timeout.
*
* Returns    : none
************************************************************************************************************************
*/

void  OSMutexPend ( OS_MUTEX  *p_mutex,
                    OS_TICK    timeout,
                    OS_OPT     opt,
                    CPU_TS    *p_ts,
                    OS_ERR    *p_err )
{
    OS_PEND_DATA  pend_data;
    OS_TCB       *p_tcb;
    CPU_SR_ALLOC();



#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return;
    }
#endif

#if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u
    if ( OSIntNestingCtr > ( OS_NESTING_CTR ) 0 )           /* Not allowed to call from an ISR                        */
    {
        *p_err = OS_ERR_PEND_ISR;
        return;
    }
#endif

#if OS_CFG_ARG_CHK_EN > 0u
    if ( p_mutex == ( OS_MUTEX * ) 0 )                      /* Validate arguments                                     */
    {
        *p_err = OS_ERR_OBJ_PTR_NULL;
        return;
    }
    switch ( opt )                                          /* Validate 'opt'                                         */
    {
    case OS_OPT_PEND_BLOCKING:
    case OS_OPT_PEND_NON_BLOCKING:
        break;

    default:
        *p_err = OS_ERR_OPT_INVALID;
        return;
    }
#endif

#if OS_CFG_OBJ_TYPE_CHK_EN > 0u
    if ( p_mutex->Type != OS_OBJ_TYPE_MUTEX )               /* Make sure mutex was created                            */
    {
        *p_err = OS_ERR_OBJ_TYPE;
        return;
    }
#endif

    if ( p_ts != ( CPU_TS * ) 0 )
    {
        *p_ts  = ( CPU_TS  ) 0;                              /* Initialize the returned timestamp                      */
    }

    CPU_CRITICAL_ENTER();
    if ( p_mutex->OwnerNestingCtr == ( OS_NESTING_CTR ) 0 ) /* Resource available?                                    */
    {
        p_mutex->OwnerTCBPtr       =  OSTCBCurPtr;          /* Yes, caller may proceed                                */
        p_mutex->OwnerOriginalPrio =  OSTCBCurPtr->Prio;
        p_mutex->OwnerNestingCtr   = ( OS_NESTING_CTR ) 1;
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = p_mutex->TS;
        }
        CPU_CRITICAL_EXIT();
        *p_err = OS_ERR_NONE;
        return;
    }

    if ( OSTCBCurPtr == p_mutex->OwnerTCBPtr )              /* See if current task is already the owner of the mutex  */
    {
        p_mutex->OwnerNestingCtr++;
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = p_mutex->TS;
        }
        CPU_CRITICAL_EXIT();
        *p_err = OS_ERR_MUTEX_OWNER;                         /* Indicate that current task already owns the mutex      */
        return;
    }

    if ( ( opt & OS_OPT_PEND_NON_BLOCKING ) != ( OS_OPT ) 0 ) /* Caller wants to block if not available?                */
    {
        CPU_CRITICAL_EXIT();
        *p_err = OS_ERR_PEND_WOULD_BLOCK;                    /* No                                                     */
        return;
    }
    else
    {
        if ( OSSchedLockNestingCtr > ( OS_NESTING_CTR ) 0 ) /* Can't pend when the scheduler is locked                */
        {
            CPU_CRITICAL_EXIT();
            *p_err = OS_ERR_SCHED_LOCKED;
            return;
        }
    }
    /* Lock the scheduler/re-enable interrupts                */
    OS_CRITICAL_ENTER_CPU_EXIT();
    p_tcb = p_mutex->OwnerTCBPtr;                           /* Point to the TCB of the Mutex owner                    */
    if ( p_tcb->Prio > OSTCBCurPtr->Prio )                  /* See if mutex owner has a lower priority than current   */
    {
        switch ( p_tcb->TaskState )
        {
        case OS_TASK_STATE_RDY:
            OS_RdyListRemove ( p_tcb );                /* Remove from ready list at current priority             */
            p_tcb->Prio = OSTCBCurPtr->Prio;           /* Raise owner's priority                                 */
            OS_PrioInsert ( p_tcb->Prio );
            OS_RdyListInsertHead ( p_tcb );            /* Insert in ready list at new priority                   */
            break;

        case OS_TASK_STATE_DLY:
        case OS_TASK_STATE_DLY_SUSPENDED:
        case OS_TASK_STATE_SUSPENDED:
            p_tcb->Prio = OSTCBCurPtr->Prio;           /* Only need to raise the owner's priority                */
            break;

        case OS_TASK_STATE_PEND:                        /* Change the position of the task in the wait list       */
        case OS_TASK_STATE_PEND_TIMEOUT:
        case OS_TASK_STATE_PEND_SUSPENDED:
        case OS_TASK_STATE_PEND_TIMEOUT_SUSPENDED:
            OS_PendListChangePrio ( p_tcb,
                                    OSTCBCurPtr->Prio );
            break;

        default:
            OS_CRITICAL_EXIT();
            *p_err = OS_ERR_STATE_INVALID;
            return;
        }
    }

    OS_Pend ( &pend_data,                                   /* Block task pending on Mutex                            */
              ( OS_PEND_OBJ * ) ( ( void * ) p_mutex ),
              OS_TASK_PEND_ON_MUTEX,
              timeout );

    OS_CRITICAL_EXIT_NO_SCHED();

    OSSched();                                              /* Find the next highest priority task ready to run       */

    CPU_CRITICAL_ENTER();
    switch ( OSTCBCurPtr->PendStatus )
    {
    case OS_STATUS_PEND_OK:                             /* We got the mutex                                       */
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = OSTCBCurPtr->TS;
        }
        *p_err = OS_ERR_NONE;
        break;

    case OS_STATUS_PEND_ABORT:                          /* Indicate that we aborted                               */
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = OSTCBCurPtr->TS;
        }
        *p_err = OS_ERR_PEND_ABORT;
        break;

    case OS_STATUS_PEND_TIMEOUT:                        /* Indicate that we didn't get mutex within timeout       */
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = ( CPU_TS  ) 0;
        }
        *p_err = OS_ERR_TIMEOUT;
        break;

    case OS_STATUS_PEND_DEL:                            /* Indicate that object pended on has been deleted        */
        if ( p_ts != ( CPU_TS * ) 0 )
        {
            *p_ts  = OSTCBCurPtr->TS;
        }
        *p_err = OS_ERR_OBJ_DEL;
        break;

    default:
        *p_err = OS_ERR_STATUS_INVALID;
        break;
    }
    CPU_CRITICAL_EXIT();
}

/*$PAGE*/
/*
************************************************************************************************************************
*                                               ABORT WAITING ON A MUTEX
*
* Description: This function aborts & readies any tasks currently waiting on a mutex.  This function should be used
*              to fault-abort the wait on the mutex, rather than to normally signal the mutex via OSMutexPost().
*
* Arguments  : p_mutex   is a pointer to the mutex
*
*              opt       determines the type of ABORT performed:
*
*                            OS_OPT_PEND_ABORT_1          ABORT wait for a single task (HPT) waiting on the mutex
*                            OS_OPT_PEND_ABORT_ALL        ABORT wait for ALL tasks that are  waiting on the mutex
*                            OS_OPT_POST_NO_SCHED         Do not call the scheduler
*
*              p_err     is a pointer to a variable that will contain an error code returned by this function.
*
*                            OS_ERR_NONE                  At least one task waiting on the mutex was readied and
*                                                         informed of the aborted wait; check return value for the
*                                                         number of tasks whose wait on the mutex was aborted.
*                            OS_ERR_OBJ_PTR_NULL          If 'p_mutex' is a NULL pointer.
*                            OS_ERR_OBJ_TYPE              If 'p_mutex' is not pointing at a mutex
*                            OS_ERR_OPT_INVALID           If you specified an invalid option
*                            OS_ERR_PEND_ABORT_ISR        If you attempted to call this function from an ISR
*                            OS_ERR_PEND_ABORT_NONE       No task were pending
*
* Returns    : == 0          if no tasks were waiting on the mutex, or upon error.
*              >  0          if one or more tasks waiting on the mutex are now readied and informed.
************************************************************************************************************************
*/

#if OS_CFG_MUTEX_PEND_ABORT_EN > 0u
OS_OBJ_QTY  OSMutexPendAbort ( OS_MUTEX  *p_mutex,
                               OS_OPT     opt,
                               OS_ERR    *p_err )
{
    OS_PEND_LIST  *p_pend_list;
    OS_TCB        *p_tcb;
    CPU_TS         ts;
    OS_OBJ_QTY     nbr_tasks;
    CPU_SR_ALLOC();



#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return ( ( OS_OBJ_QTY ) 0u );
    }
#endif

#if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u
    if ( OSIntNestingCtr > ( OS_NESTING_CTR ) 0u )          /* Not allowed to Pend Abort from an ISR                  */
    {
        *p_err =  OS_ERR_PEND_ABORT_ISR;
        return ( ( OS_OBJ_QTY ) 0u );
    }
#endif

#if OS_CFG_ARG_CHK_EN > 0u
    if ( p_mutex == ( OS_MUTEX * ) 0 )                      /* Validate 'p_mutex'                                     */
    {
        *p_err =  OS_ERR_OBJ_PTR_NULL;
        return ( ( OS_OBJ_QTY ) 0u );
    }
    switch ( opt )                                          /* Validate 'opt'                                         */
    {
    case OS_OPT_PEND_ABORT_1:
    case OS_OPT_PEND_ABORT_ALL:
    case OS_OPT_PEND_ABORT_1   | OS_OPT_POST_NO_SCHED:
    case OS_OPT_PEND_ABORT_ALL | OS_OPT_POST_NO_SCHED:
        break;

    default:
        *p_err =  OS_ERR_OPT_INVALID;
        return ( ( OS_OBJ_QTY ) 0u );
    }
#endif

#if OS_CFG_OBJ_TYPE_CHK_EN > 0u
    if ( p_mutex->Type != OS_OBJ_TYPE_MUTEX )               /* Make sure mutex was created                            */
    {
        *p_err =  OS_ERR_OBJ_TYPE;
        return ( ( OS_OBJ_QTY ) 0u );
    }
#endif

    CPU_CRITICAL_ENTER();
    p_pend_list = &p_mutex->PendList;
    if ( p_pend_list->NbrEntries == ( OS_OBJ_QTY ) 0u )     /* Any task waiting on mutex?                             */
    {
        CPU_CRITICAL_EXIT();                                /* No                                                     */
        *p_err =  OS_ERR_PEND_ABORT_NONE;
        return ( ( OS_OBJ_QTY ) 0u );
    }

    OS_CRITICAL_ENTER_CPU_EXIT();
    nbr_tasks = 0u;
    ts        = OS_TS_GET();                                /* Get local time stamp so all tasks get the same time    */
    while ( p_pend_list->NbrEntries > ( OS_OBJ_QTY ) 0u )
    {
        p_tcb = p_pend_list->HeadPtr->TCBPtr;
        OS_PendAbort ( ( OS_PEND_OBJ * ) ( ( void * ) p_mutex ),
                       p_tcb,
                       ts );
        nbr_tasks++;
        if ( opt != OS_OPT_PEND_ABORT_ALL )                 /* Pend abort all tasks waiting?                          */
        {
            break;                                          /* No                                                     */
        }
    }
    OS_CRITICAL_EXIT_NO_SCHED();

    if ( ( opt & OS_OPT_POST_NO_SCHED ) == ( OS_OPT ) 0u )
    {
        OSSched();                                          /* Run the scheduler                                      */
    }

    *p_err = OS_ERR_NONE;
    return ( nbr_tasks );
}
#endif

/*$PAGE*/
/*
************************************************************************************************************************
*                                                   POST TO A MUTEX
*
* Description: This function signals a mutex
*
* Arguments  : p_mutex  is a pointer to the mutex
*
*              opt      is an option you can specify to alter the behavior of the post.  The choices are:
*
*                           OS_OPT_POST_NONE        No special option selected
*                           OS_OPT_POST_NO_SCHED    If you don't want the scheduler to be called after the post.
*
*              p_err    is a pointer to a variable that will contain an error code returned by this function.
*
*                           OS_ERR_NONE             The call was successful and the mutex was signaled.
*                           OS_ERR_MUTEX_NESTING    Mutex owner nested its use of the mutex
*                           OS_ERR_MUTEX_NOT_OWNER  If the task posting is not the Mutex owner
*                           OS_ERR_OBJ_PTR_NULL     If 'p_mutex' is a NULL pointer.
*                           OS_ERR_OBJ_TYPE         If 'p_mutex' is not pointing at a mutex
*                           OS_ERR_POST_ISR         If you attempted to post from an ISR
*
* Returns    : none
************************************************************************************************************************
*/

void  OSMutexPost ( OS_MUTEX  *p_mutex,
                    OS_OPT     opt,
                    OS_ERR    *p_err )
{
    OS_PEND_LIST  *p_pend_list;
    OS_TCB        *p_tcb;
    CPU_TS         ts;
    CPU_SR_ALLOC();



#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return;
    }
#endif

#if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u
    if ( OSIntNestingCtr > ( OS_NESTING_CTR ) 0 )           /* Not allowed to call from an ISR                        */
    {
        *p_err = OS_ERR_POST_ISR;
        return;
    }
#endif

#if OS_CFG_ARG_CHK_EN > 0u
    if ( p_mutex == ( OS_MUTEX * ) 0 )                      /* Validate 'p_mutex'                                     */
    {
        *p_err = OS_ERR_OBJ_PTR_NULL;
        return;
    }
    switch ( opt )                                          /* Validate 'opt'                                         */
    {
    case OS_OPT_POST_NONE:
    case OS_OPT_POST_NO_SCHED:
        break;

    default:
        *p_err =  OS_ERR_OPT_INVALID;
        return;
    }
#endif

#if OS_CFG_OBJ_TYPE_CHK_EN > 0u
    if ( p_mutex->Type != OS_OBJ_TYPE_MUTEX )               /* Make sure mutex was created                            */
    {
        *p_err = OS_ERR_OBJ_TYPE;
        return;
    }
#endif

    CPU_CRITICAL_ENTER();
    if ( OSTCBCurPtr != p_mutex->OwnerTCBPtr )              /* Make sure the mutex owner is releasing the mutex       */
    {
        CPU_CRITICAL_EXIT();
        *p_err = OS_ERR_MUTEX_NOT_OWNER;
        return;
    }

    OS_CRITICAL_ENTER_CPU_EXIT();
    ts          = OS_TS_GET();                              /* Get timestamp                                          */
    p_mutex->TS = ts;
    p_mutex->OwnerNestingCtr--;                             /* Decrement owner's nesting counter                      */
    if ( p_mutex->OwnerNestingCtr > ( OS_NESTING_CTR ) 0 )  /* Are we done with all nestings?                         */
    {
        OS_CRITICAL_EXIT();                                 /* No                                                     */
        *p_err = OS_ERR_MUTEX_NESTING;
        return;
    }

    p_pend_list = &p_mutex->PendList;
    if ( p_pend_list->NbrEntries == ( OS_OBJ_QTY ) 0 )      /* Any task waiting on mutex?                             */
    {
        p_mutex->OwnerTCBPtr     = ( OS_TCB       * ) 0;    /* No                                                     */
        p_mutex->OwnerNestingCtr = ( OS_NESTING_CTR ) 0;
        OS_CRITICAL_EXIT();
        *p_err = OS_ERR_NONE;
        return;
    }
    /* Yes                                                    */
    if ( OSTCBCurPtr->Prio != p_mutex->OwnerOriginalPrio )
    {
        OS_RdyListRemove ( OSTCBCurPtr );
        OSTCBCurPtr->Prio = p_mutex->OwnerOriginalPrio;     /* Lower owner's priority back to its original one        */
        OS_PrioInsert ( OSTCBCurPtr->Prio );
        OS_RdyListInsertTail ( OSTCBCurPtr );               /* Insert owner in ready list at new priority             */
        OSPrioCur         = OSTCBCurPtr->Prio;
    }
    /* Get TCB from head of pend list                         */
    p_tcb                      = p_pend_list->HeadPtr->TCBPtr;
    p_mutex->OwnerTCBPtr       = p_tcb;                     /* Give mutex to new owner                                */
    p_mutex->OwnerOriginalPrio = p_tcb->Prio;
    p_mutex->OwnerNestingCtr   = ( OS_NESTING_CTR ) 1;
    /* Post to mutex                                          */
    OS_Post ( ( OS_PEND_OBJ * ) ( ( void * ) p_mutex ),
              ( OS_TCB      * ) p_tcb,
              ( void        * ) 0,
              ( OS_MSG_SIZE  ) 0,
              ( CPU_TS       ) ts );

    OS_CRITICAL_EXIT_NO_SCHED();

    if ( ( opt & OS_OPT_POST_NO_SCHED ) == ( OS_OPT ) 0 )
    {
        OSSched();                                          /* Run the scheduler                                      */
    }

    *p_err = OS_ERR_NONE;
}

/*$PAGE*/
/*
************************************************************************************************************************
*                                            CLEAR THE CONTENTS OF A MUTEX
*
* Description: This function is called by OSMutexDel() to clear the contents of a mutex
*

* Argument(s): p_mutex      is a pointer to the mutex to clear
*              -------
*
* Returns    : none
*
* Note(s)    : This function is INTERNAL to uC/OS-III and your application should not call it.
************************************************************************************************************************
*/

void  OS_MutexClr ( OS_MUTEX  *p_mutex )
{
    p_mutex->Type              =  OS_OBJ_TYPE_NONE;         /* Mark the data structure as a NONE                      */
    p_mutex->NamePtr           = ( CPU_CHAR     * ) ( ( void * ) "?MUTEX" );
    p_mutex->OwnerTCBPtr       = ( OS_TCB       * ) 0;
    p_mutex->OwnerNestingCtr   = ( OS_NESTING_CTR ) 0;
    p_mutex->TS                = ( CPU_TS        ) 0;
    p_mutex->OwnerOriginalPrio =  OS_CFG_PRIO_MAX;
    OS_PendListInit ( &p_mutex->PendList );                 /* Initialize the waiting list                            */
}

/*$PAGE*/
/*
************************************************************************************************************************
*                                          ADD/REMOVE MUTEX TO/FROM DEBUG LIST
*
* Description: These functions are called by uC/OS-III to add or remove a mutex to/from the debug list.
*
* Arguments  : p_mutex     is a pointer to the mutex to add/remove
*
* Returns    : none
*
* Note(s)    : These functions are INTERNAL to uC/OS-III and your application should not call it.
************************************************************************************************************************
*/


#if OS_CFG_DBG_EN > 0u
void  OS_MutexDbgListAdd ( OS_MUTEX  *p_mutex )
{
    p_mutex->DbgNamePtr               = ( CPU_CHAR * ) ( ( void * ) " " );
    p_mutex->DbgPrevPtr               = ( OS_MUTEX * ) 0;
    if ( OSMutexDbgListPtr == ( OS_MUTEX * ) 0 )
    {
        p_mutex->DbgNextPtr           = ( OS_MUTEX * ) 0;
    }
    else
    {
        p_mutex->DbgNextPtr           =  OSMutexDbgListPtr;
        OSMutexDbgListPtr->DbgPrevPtr =  p_mutex;
    }
    OSMutexDbgListPtr                 =  p_mutex;
}



void  OS_MutexDbgListRemove ( OS_MUTEX  *p_mutex )
{
    OS_MUTEX  *p_mutex_next;
    OS_MUTEX  *p_mutex_prev;


    p_mutex_prev = p_mutex->DbgPrevPtr;
    p_mutex_next = p_mutex->DbgNextPtr;

    if ( p_mutex_prev == ( OS_MUTEX * ) 0 )
    {
        OSMutexDbgListPtr = p_mutex_next;
        if ( p_mutex_next != ( OS_MUTEX * ) 0 )
        {
            p_mutex_next->DbgPrevPtr = ( OS_MUTEX * ) 0;
        }
        p_mutex->DbgNextPtr = ( OS_MUTEX * ) 0;

    }
    else if ( p_mutex_next == ( OS_MUTEX * ) 0 )
    {
        p_mutex_prev->DbgNextPtr = ( OS_MUTEX * ) 0;
        p_mutex->DbgPrevPtr      = ( OS_MUTEX * ) 0;

    }
    else
    {
        p_mutex_prev->DbgNextPtr =  p_mutex_next;
        p_mutex_next->DbgPrevPtr =  p_mutex_prev;
        p_mutex->DbgNextPtr      = ( OS_MUTEX * ) 0;
        p_mutex->DbgPrevPtr      = ( OS_MUTEX * ) 0;
    }
}
#endif

/*$PAGE*/
/*
************************************************************************************************************************
*                                                MUTEX INITIALIZATION
*
* Description: This function is called by OSInit() to initialize the mutex management.
*

* Argument(s): p_err        is a pointer to a variable that will contain an error code returned by this function.
*
*                                OS_ERR_NONE     the call was successful
*
* Returns    : none
*
* Note(s)    : 1) This function is INTERNAL to uC/OS-III and your application MUST NOT call it.
************************************************************************************************************************
*/

void  OS_MutexInit ( OS_ERR  *p_err )
{
#ifdef OS_SAFETY_CRITICAL
    if ( p_err == ( OS_ERR * ) 0 )
    {
        OS_SAFETY_CRITICAL_EXCEPTION();
        return;
    }
#endif

#if OS_CFG_DBG_EN > 0u
    OSMutexDbgListPtr = ( OS_MUTEX * ) 0;
#endif

    OSMutexQty        = ( OS_OBJ_QTY ) 0;
    *p_err             =  OS_ERR_NONE;
}

#endif                                                      /* OS_CFG_MUTEX_EN                                        */
